anticlimactic

void output_order(userid root) {
  queue<userid> roots;
  roots.push(root);
  while (!roots.empty()) {
    const userid u = roots.front();
    roots.pop();
    const EdgeSet& oe = nodes[u].outedges;
    printf("%s\n", usermap[u].c_str());
    for (EdgeSet::const_iterator i = oe.begin();
         i != oe.end(); i++) {  // \n to fit on lj
      if (--nodes[*i].indegree == 0)
        roots.push(*i);
    }
  }
}